i honestly think its to prevent the Pile of snail mail (regular mail, for those that dont know the term) that comes with registering things like this.

Man, i lost count of the 'free Pens' offers, free vacations,credit card machines, accts receivable processing, and the list goes on >>> , i get Each and Everytime i do a simple LLC or State Sole Prop DBA.

they are probably just playing the game as 'We' do with proxy email addresses.
...JUST AN OBSERVATION AND GUESS...

matcat